This mini USB camera has 2 units: a camera head and a USB video converter. The former has analog video/audio output signals,the latter converts the analog signals into digital ones with a USB protocol which allows interfacing to a computer conveniently. There are 4 wires between the 2 units.

The mini camera head comes with all the circuits for generating the standard NTSC or PAL video/audio signals. The image sensor has a built-in color filter array, for generating the color signal.